POWER INTEGRATIONS LYT2004K

The LYTSwitch™-2 family of ICs dramatically simplifies low power CC LED drivers by eliminating the optocoupler and secondary control circuitry. The family introduces a revolutionary control technique which provides accurate output current regulation, compensating for transformer and external component variations, and device parameter tolerances as well as input voltage variations. The device incorporates a high-voltage switching MOSFET, an ON/OFF control state-machine, a high-voltage switched current source for self-biasing, frequency jitter to reduce EMI, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry into a monolithic IC. This high level of integration enables cost-effective designs with very few external components, reducing solution cost and driver size. LYTSwitch-2 parts minimize energy consumption when the output is unloaded. Practical designs can easily achieve less than 30 mW no-load consumption. The 725 V power MOSFET used in LYTSwitch-2 devices increases the circuits’ ability to withstand input surge. In addition, each package is designed to maximize the creepage distance between high-voltage pins and logic level inputs. This increased pin spacing increases driver lifetime and reliability in polluted environments. These in-built protection features also protect the entire circuit from excess temperature operation, increasing lifetime in thermally challenging environments.

• Accurate CC Regulation, Meets ±3% in a Typical Design
• Controller Automatically Compensates For:
  • Transformer inductance variation
  • External component changes with temperature
  • Input line voltage variations
• Cost-Effective, Small Size Designs:
  • Eliminates the optocoupler and secondary CC control circuitry
  • Eliminates control loop compensation circuitry
  • Frequency-jitter greatly reduces EMI filter cost
  • Programmable switching frequency reduces transformer size
  • 725 V switching power MOSFET enables clampless flyback designs
• Advanced Protection/Safety Features:
  • Auto-restart protection reduces power delivered by >90% for output short-circuit and control loop faults (open and short-circuit components)
  • Hysteretic thermal shutdown – with automatic recovery
  • Meets high-voltage creepage requirements between DRAIN and all other pins both on the PCB and at the package
• EcoSmart™– Energy Efficient:
  • No-load consumption < 30 mW
  • No current sense resistors – maximizes efficiency
• Green Package:
  • All parts are halogen free and RoHS compliant

• LED bulbs, down lights, luminaires, ballasts and T8 tubes